Since I'm a user on all 4 sites, when I want to check for responses I have to individually visit each Recent Activity page. Can I have a "combined view" that aggregates data from all 4 sites on one page?

Also when checking up on a particular user, I'd like to see all his best questions and answers, not just those that relate to the current site.

I humbly disagree. If I have accounts in both places, why wouldn't I be interested in updates from both places? It would make sense to provide a single dashboard for all related sites.
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Torben Gundtofte-BruunAug 23 '10 at 14:06